1. Field of the Invention
The present invention relates to a keratotic plug remover which excellently removes keratotic plugs formed in the pores of the skin, and a method of removing keratotic plugs from the skin utilizing such a keratotic plug remover.
2. Discussion of the Background
Having conspicuous pores in the skin is-a serious skin problem, especially for women, and is mainly caused, by keratotic plugs formed in the pores of the skin. Keratotic plugs are dead epidermal cells keratinized together with sebaceous matters and dirt which plug the pores of the skin. If proper treatment is not given; not only conspicuous pores but also various skin troubles result. Accordingly, removal of keratotic plugs is advisable in view-of the health and beauty of the skin.
Ordinary face detergents, make-up removers, however, cannot sufficiently remove the keratotic plugs.
Pack preparations, which are applied to the skin and, peeled off after dried, and which generally contain a nonionic polymer such as polyvinyl alcohol and polyvinyl pyrrolidone as a major component of a film forming agent, are still not sufficiently effective for removing dirt from the skin pores and especially for removing keratotic plugs.
Thus, there remains a need for a keratotic plug remover which can effectively remove keratotic plugs formed in the pores of the skin and a method of removing keratotic plugs from the skin utilizing such plug removers.
Accordingly, it is one object of the present invention to provide novel keratotic plug removers which effectively remove keratotic plugs from the skin.
It is another object of the present invention to provide a method for removing keratotic plugs from the skin which utilized such keratotic plug removers.
These and other objects which will become apparent during the following detailed description have been achieved by the inventors discovery that a keratotic plug remover which comprises a synthetic polymer having a salt forming group can effectively remove keratotic plugs and dirt from the pores of the skin.
The salt forming group of the polymer which is useful in the present invention is not particularly limited as long as it can form a salt in the presence of an acid or a base, and anionic, cationic and amphoteric groups are suitable. Examples of the salt forming group are carboxyl, sulfonic acid group, sulfuric acid residual group (xe2x80x94OSO3H), phosphoric acid residual group (xe2x80x94OPO3H2), nitric acid residual group (xe2x80x94NO2), amino group, ammonium group, and the like. Two or more of these groups maybe present in one compound.
The polymer compound which is useful in the present invention is preferably water-soluble from the viewpoint of good appearance, but it is not necessarily water-soluble for the purpose of achieving the effects of this invention. The compounds which are not water-soluble may take the form of dispersion and/or emulsion.
Examples of the polymers useful in the present invention include: hyaluronic acid, sodium hyaluronate, sodium chondroitin sulfate which are mucopolysaccharides; alginic acid, sodium alginate, ammonium alginate, sodium carboxylmethylcellulose, and carboxymethyl amylose which are hemicelluloses. These are of natural origin or semisynthesized polymers. In this invention, synthesized polymers are more preferable. Examples of the synthesized polymers include (A) polymers of one or more monomers listed in (1) to (3) below, (B) copolymers of the monomers as listed in (1) to (3) and another monomer which has no salt forming group, such as vinyl esters of aliphatic carboxylic acid such as vinyl acetate, (meth)acrylic esters such as methyl methacrylate, alkyl vinyl ethers such as methyl vinyl ether, N-vinyl cyclic amides such as N-vinylpyrrolidone, styrene and alkyl-substituted styrene, and (C) mixtures of the above-mentioned polymers.
(1) Anionic monomers:
Acrylic acid (AA), Methacrylic acid (MA), Malaic acid, itaconic acid and the like, which are unsaturated carboxylic acid monomers or their anhydrides or their salts;
Styrene sulfonic acid, 2-Acrylamide-2-methyl propane sulfonic acid (AMPS) and the like, which are unsaturated. sulfonic acid monomers or their salts;
Vinyl phosphonic acid, Acid phosphoxyethyl (meth) acrylate and the like, which are unsaturated phosphoric monomers.
(2) Cationic Monomers
Dimethylaminoethyl acrylate (DMAEA), Dimethylaminoethyl methacrylate (DMAEMA, Dimethylaminopropylacrylamide (DMAPAAm, Dimethylaminopropyl methacrylamide (DMAPMAAm), and the like, which are (meth)acrylamides or (meth) acrylic acid esters having a dialkylamino group; Dimethylaminostyrene (DMASt), Dimethyaminomethylstyrene (DMAMSt) and the like, which are styrenes having a dialkylamino group;
4-Vinyl pyridine, 2-vinyl pyridine and the like, which are vinyl pyridines;
Quaternarized products of these with a known quatenarizing agent such as alkyl halide, benzyl halide, alkyl or aryl sulfonic acid, or dialkyl sulfate.
(3) Amphoteric Monomers
N-(3-sulfopropyl)-N-acryloyloxyethyl-N,N-dimethylammonium betaine, N-(3-sulfopropyl)-N-methacroylamidepropyl-N,N-dimethylammonium betaine, N-(3-carboxymethyl)-N-methacroylamidepropyl-N,N-dimethylammonium betaine, N-carboxymethyl-N-methacroyloxyethyl-N,N-dimethylammonium betaine.
When the salt forming group of these polymers is not ionized, it is preferred to ionize it via neutralization with known acids such as hydrochloric acid and sulfuric acid which are inorganic acids; acetic acid, propionic acid, lactic acid, succinic acid, glycol acid which are organic acids, or with known bases such as triethylamine, trimethylamine which are tertiary amines; ammonia; or sodium hydroxide.
Among the mentioned polymer compounds, preferred ones in view of the mildness to the skin and high effectiveness for removing keratotic plugs are polymers of one or more cationic monomers, copolymers between one of these polymers and an amphoteric monomer or a monomer having no salt forming groups, and mixtures of these polymers.
Preferable examples of the cationic monomers include dimethylaminoethylacrylate (DMAEA), dimethylaminoethylmethacrylate (DMAEMA), Dimethylaminopropylacrylamide (DMAPAAm), dimethylaminopropyl methacrylamide (DMAPMAAm) and the like, which are (meth)acrylic esters or (meth)acrylamides having a dialkylamino group; and quaternary compound of them which are quaternarized with a known quaternarizing agent such as alkyl halide, benzyl halide, alkyl or aryl sulfonic acid or dialkyl sulfate. Among them, especially preferred are dimethylaminoethylmethacrylate (DMAEMA) and its quaternarized products; quaternarized products of dimethylaminopropyl methacrylamide (DMAPMAAm); polymers of one or more of these monomers; copolymers between one or more of these monomers and the above-mentioned monomers; and mixtures thereof.
The molecular weight (weight average) of these polymers is preferably in the range of from 10,000 to 1,500,000, and especially from 100,000 to 1,000,000. Molecular weights less than 10,000 will result in insufficient film strength and easily breakable films upon peeling-off. Polymers having a molecular weight over 1,500,000 are difficult to manufacture.
The preferable amount of the polymer to be incorporated into the keratotic plug remover preparation according to the invention is from 0.01 to 70% by weight, preferably 5 to 40% by weight based on the total weight of the preparation.
The above-mentioned synthesized polymers are used as dissolved in a solvent. The solvent useful in this invention is volatile and is not particularly limited as long as it can stably dissolve the polymers and is safe to the skin. Examples of such solvents include water, ethanol, isopropyl alcohol (IPA) and the like. They are used singly or in combination. The amount or the solvent is modified depending on the properties of the polymer compounds, optional ingredients and forms of the preparation, and is generally from 30 to 99.99% by weight, and preferably from 60 to 95% by weight, based on the total weight of the composition.
The efficacy of the keratotic plug remover of this invention is enhanced when a pigment is further incorporated together with the mentioned polymers. The pigment is not particularly limited, and both organic and inorganic pigments can be used. Examples of the inorganic pigments are zinc oxide, titanium oxide, silica, alumina, barium sulfate, zirconium oxide, calcium carbonate, calcium silicate, ceramics, hydroxyapatite, boron nitride, sericite, mica, talc, kaolin, montmorillonite, hectorite, saponite, black iron oxide, yellow iron oxide, red iron oxide, prussian blue, ultramarine, carbon black, pearlescent pigments and so on. Examples of the organic pigments are silk powders, cellulose powders, poly (meth)acrylic ester resins, polyamide resins, polyolefin resins, polyimide resins, polyurethane resins, polyester resins, polyether resins, polyvinyl chloride resins, urea resins, polyformaldehyde resins, polycarbonate resins, polyvinylacetate resins, polyvinylidene chloride resins, polyacrylonitrile resins, polysulfone resins, polystyrene resins, polyurea resins, silicone resins, melamine resins, polytetrafluoroethylene resins, rake pigments and azo dyes.
The particle size of the pigments is from 0.001 to 1000 micrometers, and preferably from 0.01 to 500 micrometers. Particle size of less than 0.001 micrometer is not preferred because good dispersibility cannot be obtained. Particle size over 1000 micrometers is not preferred, either, because of an unfavorable sensation to the skin. The mentioned pigments can be used as a complex or a mixture of one or more, if desired. the amount of the pigment is from 0.1 to 70% by weight, preferably from 1 to 40% by weight based on the total weight of the preparation.
When an oil component is further incorporated together with the polymers, the keratotic plug remover of this invention can achieve excellent removal of keratotic plugs without giving irritation to the skin. This is because the strength of the film at which it breaks upon peeling-off can be controlled by the oil component.
The oil component which is useful in this invention is a glycerol derivative represented by formula (I): 
wherein one of Z1 and Z2 represents R2xe2x80x94Yxe2x80x94 and the other represents a hydroxyl group or R3xe2x80x94Yxe2x80x94, and R1, R2 and R3 independently represent a hydrocarbon group, the total carbon number of which ranges from 13 to 40, and the hydrocarbon group may or may not be substituted by a silicone residual group, Y and Y independently represent an oxygen atom or a group xe2x80x94COOxe2x80x94, (a carbonyl group in which the C atom is bonded to R1, R2, or R3). Other oily ingredients which are generally incorporated into cosmetic preparations can also be used. Examples of the oil component which is useful in this invention include vegetable oils such as avocado oil, tsubaki oil, macadamia rut oil, olive oil and jojoba oil; animal oils and fats such as beef tallow, lard and egg yolk fat; aliphatic acids such as oleic acid and isostearic acid; alcohols such as hexadecyl alcohol and oleyl alcohol; esters such as cetyl 2-ethylhexanoate, 2-ethylhexyl palmitate, 2-octyldodecyl myristate, neopentyl glycol di-2-ethyl hexanoate, 2-octyldodecyl oleate, isopropyl myristate, glycerol triisostearate, mono-2-ethylhexanoic glyceryl di-paramethoxycinnamate; and hydrocarbons such as dimethylpolysiloxane, dimethyl cyclopolysiloxane, methylphenyl polysiloxane, methylhydrogen polysiloxane, octanethyl cyclotetrasiloxane, octamethyl cyclopentasiloxane, decamethylcyclopentasiloxane, liquid paraffin, squalane, vaseline and solid paraffin.
Among these oil components, glycerol derivatives of formula (1) which are liquid at 20xc2x0 C. are preferred, and particularly, tri-2-ethylhexanoic glycerol, 1-isostearoyl-3-myristoyl glycerol, 2-ethylhexanoic diglyceride, 1-hexyl-3-undecanethylhexasiloxy propynyl glycerol are most preferred.
The amount of the oil components to be incorporated into the keratotic plug remover of this invention is from 0.5 to 30% by weight, preferably, 1 to 15% by weight based on the total weight of composition.
The keratotic plug remover preparation of this invention can further contain optional ingredients which are generally incorporated into cosmetic preparations. Examples of such optional ingredients include ethylene glycol, diethylene glycol, triethylene glycol and higher polyethylene glycols; propylene glycol, dipropylene glycol and higher polypropylene glycols, 1,3-butylene glycol, 1,4-butylene glycol and other butylene glycols; glycerol, diglycerol and higher polyglycerols; sugar alcohols such as sorbitol, mannitol, xylitol and maltitol; ethylene oxides (hereinafter referred to as EO) such as glycerols; addition products of propylene oxide (hereinafter referred to as PO); EO or PO adducts of sugar alcohols; monosaccharides such as galactose, glucose and fructose, and their EO or PO adducts; polysaccharides such as maltose and lactose, and their EO or PO adducts (polyols); surfactants such as POE alkyl ethers (POE is polyol ethylene), POE branched alkyl ethers, POE sorbitan esters, POE glycerol fatty acid esters, POE hydrogenated castor oil, sorbitan ester, glycerol fatty acid esters and polyglycerol fatty acid ester; drugs such as vitamins, antiphlogistics, activators, UV absorbers and the. like; water-swelling clay minerals such as montmorillonite, saponite and hectorite; polysaccharides such as carageenan, xanthangum, sodium alginate, pullulan, methylcellulose, carboxymethylcellulose, hydroxyethylcellulose and hydroxypropylcellulose; synthetic polymers such as carboxyvinyl polymers, polyvinyl pyrrolidones and polyvinyl alcohols. They are incorporated into the preparation of the present invention in such amounts that will not impede the effects of the invention. In particular, when polyols are used, they are preferably incorporated by 0.01 to 50% by weight based on the total preparation. The keratotic plug remover according to this invention may take a form of a poultice using cotton cloth, rayon cloth, tetron cloth, nylon cloth, either woven or non-woven, or using a plastic film sheet, beside pack preparations.
The keratotic plug remover of this invention can be manufactured according to conventional processes for the manufacture of ordinary packs and poultice.
The manner of removing keratotic plugs by the use of the keratotic plug remover of the invention is the same as the manner of using ordinary packs and poultice. Namely, when a pack preparation is used, it is first applied to the part of the skin which has keratotic plugs, particularly likely to the nose, chin and forehead, and after dried, it is peeled off.
Since the keratotic plug remover of this invention effectively removes keratotic plugs, the conspicuousness of the skin pores is mitigated, skin pores are maintained clean, and healthy skin can be obtained. Further, the remover of this invention does not hurt the skin.
Other features of the invention will become apparent in the course of the following descriptions of exemplary embodiments which are given for illustration of the invention and are not intended to be limiting thereof.